The field of the present invention is swivel joint plumbing assemblies.
In plumbing systems, it is frequently necessary or convenient for a section of pipe to be able to swivel with respect to an adjoining section, especially when the two pipe sections are joined through an elbow fitting or angular joint. For example, in underground lawn sprinkler plumbing systems, a sprinkler head is connected to an underground pipe through a sprinkler riser pipe. However, the permanent position of the sprinkler head generally cannot be determined until after the final grade level has been established. Although a fixed joint may be used to connect a sprinkler head to an underground pipe, it an provide no adjusting movement for positioning the sprinkler head during final grading. This can result in an out of position sprinkler head, or undue stress on the sprinkler riser and the joints, if the sprinkler head is forced into position, or if it is displaced by vehicle or foot traffic.
Although several swivel joints have been known in the past, they generally have one or more disadvantages, including complex design and high cost, insufficient reliability in preventing leaks, difficult and time consuming assembly, corrosion and degradation problems, etc.